Guide to working with corrosive substances.

A Guide to
Working with
Corrosive Substances
Thomas O’Connell
Series Editor
N. C. Department of Labor
Division of Occupational Safety and Health
1101 Mail Service Center
Raleigh, NC 27699- 1101
Cherie K. Berry
Commissioner of Labor
Acknowledgments
This edition of A Guide to Working with Corrosive Substances is
largely based on an earlier edition written by L. A. Weaver
Company, 308 East Jones Street, Raleigh, North Carolina. The L.
A. Weaver Company specializes in occupational safety.
Additional material was provided by North Carolina Department
of Labor Health Standards Officer J. Edgar Geddie, Ph. D.
Thank you to Tim Phillips, State Director of the Office of Motor
Carriers with the Federal Highway Commission of the USDOT,
and Cara Lucas, a NERL Environmental Compliance Officer
with EPA, for their review of the associated material.
This guide is intended to be consistent with all existing OSHA
standards; therefore, if an area is considered by the reader to
be inconsistent with a standard, then the OSHA standard
should be followed.
To obtain additional copies of this book, or if you have ques-tions
about N. C. occupational safety and health standards
or rules, please contact:
N. C. Department of Labor
Bureau of Education, Training and Technical Assistance
1101 Mail Service Center
Raleigh, NC 27699- 1101
Phone: ( 919) 807- 2875 or 1- 800- NC- LABOR
____________________
Additional sources of information are listed
on the inside back cover of this book.
____________________
The projected cost of the OSHNC program for federal fiscal year 2002– 2003 is $ 13,130,589.
Federal funding provides approximately 37 percent ($ 4,920,000) of this total.
Printed 7/ 99, 1M
N. C. Department of Labor
Occupational Safety and Health Program
Cherie K. Berry
Commissioner of Labor
OSHA State Plan Designee
Allen McNeely
Deputy Commissioner for Safety and Health
Kevin Beauregard
Assistant Deputy Commissioner for Safety and Health
Contents
Part Page
Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
1 What Are Corrosives? . . . . . . . . . . . . . . . . . . . . . . . . .11
2 What Regulations Protect Us
against Corrosives?. . . . . . . . . . . . . . . . . . . . . . . . . . .17
3 How Do Corrosives Harm Us and
How Can We Protect Ourselves?. . . . . . . . . . . . 12
Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
iii
Foreword
Employers must be aware of workplace hazards fac-ing
their employees and take appropriate action to min-imize
or eliminate exposure to these hazards. A Guide
to Working with Corrosive Substances discusses precau-tions
that can prevent serious health risks to workers
due to exposure to corrosives. Corrosive chemicals are
essential to many work processes; however, they can
enter the body through ingestion, inhalation, or contact
with the skin and eyes.
Employee exposure to corrosives must be evaluated
to determine the need for engineering and administra-tive
controls as well as the need for personal protective
equipment. The results from injuries can be severe and
even fatal. Mists produced by liquids can result in lung
damage if inhaled, serious burns or irritation can be the
result of accidental contact to the skin or eyes, and lung
and skin cancer have been linked to chromic acid.
Additional threats to employees are posed by the ease
with which many corrosive chemicals ignite, explode, or
react to incompatible substances.
In North Carolina, N. C. Department of Labor inspec-tors
enforce the federal Occupational Safety and Health
Act ( OSHA) through a state plan approved by the U. S.
Department of Labor. The N. C. Department of Labor’s
Division of Occupational Safety and Health ( OSHNC)
offers many educational programs to the public and
produces publications, including this guide, to help
inform people about their rights and responsibilities
regarding occupational safety and health.
iv
As you look through this guide, please remember that
OSHA’s mission is greater than just enforcement. An
equally important goal is to help citizens find ways to
create safe and healthy workplaces. Reading and using
the information in this booklet, like other educational
materials produced by the North Carolina Department
of Labor, can help.
Cherie K. Berry
Commissioner of Labor
v
1
What Are Corrosives?
Information about Corrosives from the
Department of Transportation
The United States Department of Transportation
( DOT) regulations consider a corrosive material to be
a liquid or solid that causes visible destruction or irre-versible
alterations in human skin tissue at the site of
contact, or in the case of leakage from its packaging, a
liquid that has a severe corrosion rate on steel. The DOT
further develops this definition by offering the following:
1. A material is considered to be destructive or to
cause irreversible alteration in human skin tissue if
when tested on the intact skin of the albino rabbit
the structure of the tissue at the site of contact is
destroyed or changed irreversibly after an exposure
period of four hours or less.
2. A liquid is considered to have a severe corrosion
rate if its corrosion rate exceeds 0.250 inches per
year on steel [ SAE 1020 ( Society of Engineers)] at
a test temperature of 130° F.
In most instances, corrosive materials may be identi-fied
by the label and/ or placard ( required by the DOT)
shown in figure 1.
Information about Corrosives from the
Environmental Protection Agency
The Environmental Protection Agency ( EPA), in regulat-ing
hazardous waste, uses pH as the criterion for determin-ing
if a substance is corrosive. Wastes with a pH of less
than 2.0 or greater than 12.5 are considered to be corrosive.
1
Figure 1
DOT Label for Corrosives
The EPA defines corrosive wastes to include ( 1) aque-ous
waste exhibiting a pH of less than or equal to 2 or
greater than or equal to 12.5 and ( 2) liquid waste capable
of corroding steel at a rate greater than 0.250 inches per
year ( 1/ 4 inches per year). The EPA chose pH as one
barometer of corrosivity because waste exhibiting low or
high pH can cause harm to human tissue, promote the
migration of toxic contaminants from other waste, react
dangerously with other waste, and harm aquatic life. The
EPA chose metal corrosion rate as its other barometer of
corrosivity because waste capable of corroding metal can
escape from the containers in which it is segregated and
liberate other waste.
The percent of acidity/ alkalinity provides an indica-tion
of the capacity of a waste to resist a change in pH.
That measurement aids in the assessment of the hazard
presented by a waste over the long term. However, it
adds little to the assessment of the hazard posed by
2
CORROSIVE
the waste during transportation, storage, and initial
disposal. Furthermore, because the capacity of a waste
to retain low or high pH is as much a function of its
disposal or storage environment as of its percent of
acidity/ alkalinity, there is no scientifically valid basis
upon which to establish hazardous threshold levels of
percent of acidity/ alkalinity. ( For additional information
see 40 CFR 261.22.)
All corrosive materials and solutions have the EPA
Hazardous Waste Number D002. The following are
some of the more commonly used corrosives:
Information about Corrosives from
Consensus Standard- Setting
Organizations
In 1956, the United Nations Committee of Experts on
the Transport of Dangerous Goods established a definition
of corrosives that is used by consensus standard setting
organizations, such as the International Labor Organiza-tion
and the Intergovernmental Maritime Organization.
[ Corrosives] are substances which, by chemical action
will cause severe damage when in contact with living
tissue or, in the case of leakage, will materially dam-age
or even destroy other freight or the means of
transport; they may also cause other hazards.
Another standard setting body, the Council of Europe,
3
• Acetic Acid
• Ammonium Hydroxide
• Chromic Acid
• Hydrobromic Acid
• Hydrochloric Acid
• Hydrofluoric Acid
• Nitric Acid
• Oleum
• Perchloric Acid
• Phosphoric Acid
• Potassium Hydroxide
• Sodium Hydroxide
• Sulfuric Acid
has established the following general classes of corrosives:
• Acids and Anhydrides
• Alkalis
• Halogens and Halogen Salts
• Organic Halides, Organic Acid Halides, Esters and
Salts
• Miscellaneous corrosive substances
The chemicals most often found in these classes are
listed in table 1.
Table 1
Council of Europe Corrosive Classification
4
Acids and Anhydrides:
Acetic Acid, Acetic Anhydride, Chlorosulphonic Acid, Chronic Acid,
Dichloroacetic Acid, Fluoboric Acid, Fluosilicic Acid*, Hydrobromic
Acid*, Hydrochloric Acid*, Hydrofluoric Acid*, Hydriodic Acid*,
Nitric Acid ( over 20%), Perchloric Acid ( over 10%), Phosphoric
Pentoxide, Priopionic Anhydride, Sulphuric Acid ( over 15%),
Oleum ( Fuming Sulphuric Acid), Trichloroacetic Acid
Alkalis:
Ammonium Hydroxide ( over 15% by weight of gas), Potassium
Hydroxide ( caustic potash), Sodium Hydroxide ( over 5%, caustic
soda)
Halogens and Halogen Salts:
Aluminum Chloride, Ammonium Difluoride, Antimony Trichloride
and Pentachloride, Bromine, Phosphorus Oxycholoride,
Phosphoryl Chloride, Phosphorus Trichloride and Pentachloride,
Potassium Difluoride, Sodium Difluoride, Sodium Hypochlorite,
Stannic Chloride, Sulphur Tetrachloride, Sulphuryl Chloride,
Thionyl Chloride, Titanium Tetrachloride, Zinc Chloride
Organic Halides, Organic Acid Halides, Esters and Salts:
Acetyl Chloride, Allyl Iodide, Benzoyl Chloride, Benzylamine,
Benzyl Chloroformate, Chloroacetyl Chloride
Miscellaneous Corrosive Substances:
Ammonium Polysulfide, 2- Chlorobenzadehyde, Hydrazine
( 1%– 4%), Hydrogen Peroxide ( over 20%), Silver Nitrate
* Over 25 percent concentration; Note: Mecuric Chloride, commonly called “ Corrosive
Sublimate,” is not considered to be a corrosive substance.
Acids and Bases
Acids and bases are a part of the classification of cor-rosives
and are chemicals that pose especially severe
risks if personal contact is made with them. An impor-tant
first step in understanding the effects of acids and
bases is clearly distinguishing the two terms. Acids are
those substances that yield hydrogen ions ( H+) in an
aqueous solution. Basic substances yield hydroxide ions
( OH–) in an aqueous solution. When acids and bases
are mixed they neutralize each other, producing salts.
The resultant solution has a salty taste and none of the
properties of either acids or bases.
Bases are also known as alkalis, caustics, or hydrox-ides.
As previously noted, both acids and bases are in a
broader group of materials known as corrosives. The
scale in table 2 illustrates the distinction.
Table 2
pH Scale
Substances with a pH of less than 7 are said to be
acidic. If the substance has a pH of more than 7, it is
basic. A neutral substance has a pH of 7.
5
RED GREEN BLUE
0 __________________________ 7 _________________________ 14
Acid Base
Caustic
Alkali
Hydroxide
NEUTRAL
Other distinguishing characteristics between acids
and bases include distinctions made by effects. Acids
are chemical compounds that show in water solution a
sharp taste. ( Of course, you should never actually taste
an acid to verify its effect.) Acids have corrosive action
on metals and turn certain blue vegetable dyes red. An
acid will turn blue litmus paper red.
Bases are chemicals that in solution are soapy to the
touch and turn red vegetable dyes blue. Red litmus
paper is turned blue by a base.
6
2
What Regulations Protect Us
against Corrosives?
The United States Department of
Transportation
Specific Department of Transportation ( DOT) regula-tions
regarding corrosives are in the Code of Federal
Regulations ( 49 CFR). Among DOT regulations are
requirements for the packaging and loading of corrosives
and guidelines for accidents where corrosives are
involved ( including the subject of leaking cargo tanks).
Regarding packaging, DOT requirements for
corrosives cover the outage. The expansion traits of the
liquid and the maximum increase of temperature to
which it will be subjected in transit determine the proper
vacant space ( outage or ullage) in the package. ( As a gen-eral
rule, sufficient outage must be provided so that the
packaging will not be liquid full at 130° F for packages of
less than 110 gallons, and for tank cars not less than 2
percent of the total volume). DOT regulations also apply
to the methods of closing and cushioning packaging and
the types of containers that may be used for corrosives.
The following summary of DOT regulations offers
general guidance regarding the loading of corrosive
liquids:
In general, individual carboys and frangible contain-ers
[ containers capable of being broken] of corrosive
liquids, including charged electric storage batteries,
must, when loaded by hand, be individually loaded
into and unloaded from any motor vehicle in which
they are to be transported. All reasonable precautions
must be taken to prevent the dropping of any such
7
containers or batteries containing corrosive liquids. No
such container or battery may be loaded into a motor
vehicle having an uneven floor surface. It shall be per-missible
to load corrosive liquids, more than one tier
high above any floor only if such carboys or other con-tainers
are boxed or crated, or are in barrels or kegs.
No carboy or other container of nitric acid shall be
loaded above any container containing any other kind of
material. The loading of carboys or other containers of
nitric acid shall be limited in height to two tiers.
The North Carolina Department of
Labor, Division of Occupational Safety
and Health
Safety and health standards enforced in North
Carolina must afford protection to employees which is
at least as effective as the protection afforded to
employees by federal occupational safety and health
standards. Each employer is responsible for knowing
the standards which apply to its industry.
The standards that apply to general industry and to
the construction industry in our state are published.
Standards may be found within the Code of Federal
Regulations ( CFR) 29 CFR 1910 for general industry
and 29 CFR 1926 for the construction industry. They
are also published under the titles of North Carolina
OSHA Standards for General Industry and North
Carolina Occupational Safety and Health Standards for
the Construction Industry.
The published standards and information, including
interpretations of the standards, may be obtained by
contacting the North Carolina Department of Labor,
Division of Occupational Safety and Health. ( See the
inside back cover of this guide for the address and tele-phone
number.)
8
Below, a list identifies ( but does not quote) statutes
and standards that afford employees protection against
hazards, including corrosives. The list is intended as
illustrative and representative rather than comprehen-sive.
N. C. Gen. Stat. 95- 129( 1)— requires each employer to
provide its employees work conditions and a workplace
free from recognized hazards which are likely to cause
serious physical harm.
29 CFR 1910- 94( d)— Ventilation— Open surface
tanks— includes ( but is not limited to) requirements for
ventilation and personal protection equipment ( such as
protective clothing and emergency showers and
fountains) for employees who work around open surface
tanks. ( See also 29 CFR 1910.261( g)( 18)( i); 29 CFR
1910.262( pp); 29 CFR 1910.268( b)( 2); 29 CFR
1910.111( b)( 10)( iii); 29 CFR 1910.111( b)( 10)( iv).)
29 CFR 1910.132— Personal Protective Equipment—
General requirements— requires protection for employ-ees’
eyes, face, head, and extremities in the presence of
hazards which require such protection, including ( but
not limited to) chemical hazards and hazards encoun-tered
through absorption, inhalation, or physical
contact. ( See also 29 CFR 1926.28.)
29 CFR 1910.133— Personal Protective Equipment—
Eye and face protection— requires protection against
liquids and other hazards to the eyes and face. ( See also
29 CFR 1926.102.)
29 CFR 1910.134— Personal Protective Equipment—
Respiratory protection— includes ( among other
pertinent subjects) the selection, fitting, and care for
respirators, and instructions to employees about the use
of respirators. ( See also 29 CFR 1926.103.)
29 CFR 1910.262( nn)— Special Industries— Textiles—
Acid carboys— regulates the safe removal of acid from
carboys.
9
29 CFR 1910.1000— Toxic and Hazardous
Substances— Air contaminants— identifies materials
and sets time limits for each material identified, beyond
which employees may not be exposed. ( See also 29 CFR
1926.55— Gases, vapors, fumes, dusts, and mists.)
29 CFR 1910.1200— Hazard Communication
Standard— requires that employees be informed of
chemical hazards in their workplace. ( See also 29 CFR
1926.59.) Some highlights of the standard follow:
✦ Employers must develop and implement a written
hazard communication program and make that
program available to employees.
The program must list all hazardous chemicals
known to be in the workplace and tell employees
about non- routine tasks ( such as cleaning out
tanks) which might expose them to the
hazardous chemicals.
✦ Containers of hazardous chemicals must be
labeled. The label must identify the chemical, its
manufacturer, and appropriate hazard warnings.
Employees must be trained to read such labels.
✦ Employers must have a material safety data sheet
( MSDS) for each hazardous chemical in its work-place.
The MSDS must include ( among other things):
the identity used on the container label; common
name and names of chemical ingredients in the
hazardous chemical; physical and chemical char-acteristics
( such as vapor pressure and flash
point); physical hazards ( such as potential for
fire, explosion, and reactivity to other substances
which are incompatible); health hazards ( such as
signs and symptoms of exposure); how the chem-ical
can enter your body; permissible exposure
limits; whether the chemical will cause cancer;
precautions for safe handling and use ( including
10
protective measures); emergency and first aid
procedures; when the MSDS was prepared or
last changed; the name and telephone number of
the manufacturer or other source which can
provide additional information ( including emer-gency
procedures).
✦ The MSDSs must be readily accessible to employees
during each work shift. Employees must be taught
to use them.
✦ Employees must be informed of the location of
hazardous chemicals.
✦ Employees must be trained in: how to detect the
presence of a hazardous chemical; its health haz-ards;
and protective measures ( including work
practices, personal protective equipment, and
emergency procedures).
11
3
How Do Corrosives Harm Us
and How Can We Protect
Ourselves?
How Corrosives Harm Us
Most commonly, the eyes, skin and digestive system
are the parts of the body affected by corrosive
chemicals. Causes include:
splashes during decanting
spills while carrying containers
splashes from reactions
vapors or streams from leaking containers
The severity is dependent primarily upon the concen-tration
of the chemical and the duration of contact.
With respect to the severity of chemical burns from
acids and alkalis, burns from alkalis tend to be the more
severe. An alkali in contact with human tissue may form
an albuminate ( clot or mass) and, with natural fats,
forms soaps. Tissue is gelatinized to form soluble com-pounds
resulting in deep and painful destruction.
Acids tend to harden the skin and produce pain at the
site of contact. Thus, they often give a quicker warning
of injury than do alkalis. First aid includes immediate
irrigation with plain water for at least 15 minutes.
In addition, mists produced by liquids can result in
lung damage if inhaled. Routine or accidental contact of
corrosives with the skin or eyes can result in serious
burns and irritation. Some acid mists, such as sulfuric,
can corrode teeth over an extended period of time.
Chromic acid is particularly dangerous and has been
linked to lung and skin cancer.
12
How We Can Protect Ourselves—
Evaluating the Workplace
Corrosive substances which present potential prob-lems
should be studied in detail to determine the
nature and seriousness of the problems they present.
A large part of this evaluation should consist of air sam-pling
conducted by an industrial hygienist or a person
trained in air sampling techniques. The possibility of
exposing employees to corrosives should be evaluated to
determine the needs for controls and personal
protective equipment.
Acids commonly found in industries include:
Industrial processes that use acids include:
metal cleaning, pickling, and etching
electrolysis
electroplating
battery making
paper making
chemical syntheses
Alkalis commonly found in industries include:
13
acetic
chromic
formic
hydrochloric
nitric
oxalic
perchloric
picric
phosphoric
sulfuric
ammonium hydroxide
barium
barium hydroxide
calcium chloride
calcium oxide ( quick-lime)
calcium sulfide
potassium hydroxide
sodium carbonate
( soda ash)
sodium hydroxide ( lye
or caustic soda)
sodium sulfide
Tests and Training for Employees Who
Work Near Corrosives
Recommended tests for employees exposed to corrosives
include pulmonary function tests, particularly forced vital
capacity ( FVC) and forced expiratory volume for one sec-ond
( FEV 1 ) and their ratio ( FEV 1 / FVC) on a scheduled
basis. Employees should be advised of the health hazards
posed by the particular corrosives with which they work.
They should be instructed in the proper procedures for
handling, transporting, and storing corrosives.
Training in the use of personal protective equipment
and the operation of engineering controls should also be
required.
Engineering and Administrative Controls
Engineering and administrative controls can be used
to reduce employee exposure to corrosive mists or dusts
in the air and to lessen the hazard of direct contact of
corrosives with the skin and eyes.
Engineering controls include:
local exhaust ventilation ( hoods or process enclosures)
dilution ventilation, or
a combination of the above
Administrative controls include:
eliminating the use of a particular corrosive
replacing one corrosive with a less toxic one
instituting procedures to reduce accidents associat-ed
with the handling, transporting, and storing of
corrosives
limiting employees’ exposure time to vapors, mists,
or dusts
14
One example of an administrative control is a precau-tion
to be taken when acids and water are mixed. The
acids should always be poured into the water, never the
opposite. This lessens the danger of acid being splashed
and of spattering from its contact with the water.
Figure 2 depicts apparatus designed for handling cor-rosive
liquids.
Personal Protective Equipment
When engineering and administrative controls have
failed to prevent or limit employees’ exposures, personal
protective equipment should be used. Depending on the
use of corrosives, the following types of equipment may
be required:
gloves and aprons for handling corrosives
eye and face protection against splashes
respirators for emergency or short- term use where
high concentrations of corrosives are present in the
air, and
protective shoe coverings
Emergency Wash Facilities
Additionally, emergency wash, routine washing facili-ties,
and overhead showers should be present in each
department or work area where corrosives are used.
The facilities should be in good working condition and
simple to operate. They should provide for a minimum
of 15 minutes of copious water flow. Table 3 summarizes
the requirements for eyewash and safety showers in
accordance with standards of the American National
Standards Institute ( ANSI Z358.1- 1990).
15
Figure 2
Apparatus for Handling Corrosive Liquids
16
Drum Pump Carboy Pump
Manual Pumps
Small
Bottle Tilter Carboy Tilter
Dispensing Aids
Drum Tilter Drum Dolly
Drum Handlers
17
Table 3
Summary of ANSI Z358.1- 1990— Key Requirements
Physical Features
Water column between 82"
and 96" within 20" mini-mum
diameter column at
60" above surface. Should
deliver 30 gallons per
minute ( gpm). Enclosures,
if used, require minimum
34" unobstructed diameter.
Flow rate of 0.4 gpm for 15
minutes required. Water
nozzles 33 to 45 inches
above floor and 6 inches
from wall or obstruction.
Not addressed.
Flow rate of 3.0 gpm for 15
minutes required. Water
nozzles 33 to 45 inches
above floor and 6 inches
from wall or obstruction.
Flow rate of 3.0 gpm
required.
Must meet physical
requirements of component
parts.
Equipment Type
Emergency
showers
Plumbed and
self- contained
Personal
eyewashers
Eye/ face
washes
Hand- held
drench hoses
Combination
units
Loca- Main- Training
tion tenance
* 1 * 3 * 6
* 1 * 4 * 6
* 2 * 5 * 6
* 1 * 3 * 6
* 1 * 3 * 6
* 1 * 3 * 6
*( 1) Accessible within 10 seconds and not over 100 feet from hazard.
*( 2) Not specified but recommended to be placed in vicinity of potentially
hazardous area.
*( 3) Activated weekly to flush lines and verify operation.
*( 4) Plumbed units activated weekly to flush lines and verify operation; self-contained
units- in accordance with manufacturer’s instructions.
*( 5) Inspected and maintained in accordance with manufacturers’ instructions.
*( 6) Required for all employees who might be exposed to a chemical splash.
18
Figure 3 provides examples of personal protective
equipment and emergency wash facilities.
Figure 3
Minimum Protective Equipment and Facilities
Chemical Goggles
Safety Goggles With
Full Face Shield
Eye/ Face Protectors
For Severe Exposures,
Chemical Goggles
With Full Face Shield
19
Personal Protective Equipment and Facilities
Checklist
In the checklist below, each item should be answered
“ yes.”
Are protective measures in place which:
Prevent skin, eye, and mucous membrane contact?
Provide personal protective equipment for body,
feet, head, hand/ arm, and eye/ face?
Provide properly maintained eyewash/ safety
showers for emergency use?
Ensure that workers are adequately informed and
trained as to precautions and controls?
Provide and require the use of personal hygiene
facilities at the conclusion of the work shift, prior
to breaks and meals?
Maintain corrosives in closed systems where possi-ble?
Ensure the avoidance of contact between
corrosives and other incompatible substances?
Provide for labeling on all containers as to their
content?
Provide ventilation, especially if corrosive gases or
dusts are present?
Provide fire preventive and protective measures if
contact with corrosives causes a fire risk?
Determine what risks from corrosives might be
generated from normal and abnormal
circumstances before a new process is introduced?
Ensure that acids are stored in fire- resistant
buildings with acid- resistant floors?
20
Provide storage areas with secondary containment
and proper drainage?
Provide acid- resistant electrical installations in
storage areas?
Protect glass and plastic containers against
impact?
Ensure that all containers are stored off the floor,
to facilitate flushing?
Require dispensing from larger containers with
carboy tilters and/ or pumps?
Terms
Albuminate. A water- soluble protein, widely occurring
in natural products such as milk, blood serum, and
eggs. It readily combines irreversibly to form a clot or
mass by the application of heat.
Anhydride. A chemical compound derived when a mole-cule
of water is eliminated from an acid.
Aqueous. Of, like, or formed by water.
Carboy. A large glass bottle, enclosed in a basketwork
or a wooden crate, and used for corrosive liquids.
Coefficient of Expansion. A coefficient for a substance,
which determines the extent which a solid body or gas
will expand when heat is applied.
Council of Europe. A consensus standard- setting orga-nization.
Ester. Organic compounds ( those containing carbon)
corresponding to an inorganic salt and formed by the
reaction of an acid and an alcohol.
Halide. A compound containing two elements of the
halogens.
Halogen. One of the very active chemical elements of
Group VII A of the periodic table: fluorine, chlorine,
bromine, iodine, astatine.
ILO. International Labor Organization— a consensus
standard- setting organization.
IMO. Intergovernmental Maritime Organization—
a consensus standard- setting organization.
Litmus Paper. Strips of paper containing blue
amorphous powder. The paper changes color with the
acidity or alkalinity of a solution— red at pH 4.5, blue at
pH 8.3.
21
Negative Logarithm. A common logarithm is the index
of a power to which the base 10 must be raised to equal
the number. A negative logarithm is when the charac-teristic
is less than one. Example:
Log 10 ( x) = 0.0254 means 10x = 0.254
x = - 1.59517
Outage. A vacant space left in an enclosed container to
allow for substances with high coefficients of expansion
to expand as they are heated. Such substances include
compressed gases, corrosives, and flammables. The
terms “ freeboard” and “ ullage” are also used.
pH Value. The strength of an acid or base is expressed
by the pH value. The pH is the negative logarithm of
the hydrogen ion concentration and will usually be in
the range of 1– 13. This is because the actual hydrogen
ion concentration values would otherwise cover too wide
of a range to provide meaningful data.
22
The following industry guides are available from the N. C. Department of Labor’s Division of Occupational
Safety and Health:
1# 1. A Guide to Safety in Confined Spaces
1# 2. A Guide to Procedures of the Safety and Health Review Board of North Carolina
1# 3. A Guide to Machine Safeguarding
1# 4. A Guide to OSHA in North Carolina
1# 5. A Guide for Persons Employed in Cotton Dust Environments
1# 6. A Guide to Lead Exposure in the Construction Industry
1# 7. A Guide to Bloodborne Pathogens in the Workplace
1# 8. A Guide to Voluntary Training and Training Requirements in OSHA Standards
1# 9. A Guide to Ergonomics
# 10. A Guide to Farm Safety and Health
# 11. A Guide to Radio Frequency Hazards With Electric Detonators
# 12. A Guide to Forklift Operator Training
# 13. A Guide to the Safe Storage of Explosive Materials
# 14. A Guide to the OSHA Excavations Standard
# 15. A Guide to Developing and Maintaining an Effective Hearing Conservation Program
# 17. A Guide to Asbestos for Industry
# 18. A Guide to Electrical Safety
# 19. A Guide to Occupational Exposure to Wood, Wood Dust and Combustible Dust Hazards
# 20. A Guide to Crane Safety
# 21. A Guide to School Safety and Health
# 23. A Guide to Working With Electricity
# 25. A Guide to Personal Protective Equipment
# 26. A Guide to Manual Materials Handling and Back Safety
# 27. A Guide to the Control of Hazardous Energy ( Lockout/ Tagout)
# 28. A Guide to Eye Wash and Safety Shower Facilities
# 29. A Guide to Safety and Health in Feed and Grain Mills
# 30. A Guide to Working With Corrosive Substances
# 31. A Guide to Formaldehyde
# 32. A Guide to Fall Prevention in Industry
# 33. A Guide to Office Safety and Health
# 34. A Guide to Safety and Health in the Poultry Industry
# 35. A Guide to Preventing Heat Stress
# 36. A Guide to the Safe Use of Escalators and Elevators
# 37. A Guide to Boilers and Pressure Vessels
# 38. A Guide to Safe Scaffolding
# 39. A Guide to Safety in the Textile Industry
# 40. A Guide to Emergency Action Planning
# 41. A Guide to OSHA for Small Businesses in North Carolina
Occupational Safety and Health ( OSH)
Sources of Information
You may call 1- 800- NC- LABOR ( 1- 800- 625- 2267) to reach any division of the N. C. Department of Labor; or visit the
NCDOL home page on the World Wide Web, Internet Web site address: http:// www. nclabor. com.
N. C. Division of Occupational Safety and Health
Mailing Address: Physical Location:
1101 Mail Service Center 111 Hillsborough St.
Raleigh, NC 27699- 1101 ( Old Revenue Building, 3rd Floor)
Local Telephone: ( 919) 807- 2900 Fax: ( 919) 807- 2856
For information concerning education, training and interpretations of occupational safety and health standards contact:
Bureau of Education, Training and Technical Assistance
Mailing Address: Physical Location:
1101 Mail Service Center 111 Hillsborough St.
Raleigh, NC 27699- 1101 ( Old Revenue Building, 4th Floor)
Telephone: ( 919) 807- 2875 Fax: ( 919) 807- 2876
For information concerning occupational safety and health consultative services and safety awards programs contact:
Bureau of Consultative Services
Mailing Address: Physical Location:
1101 Mail Service Center 111 Hillsborough St.
Raleigh, NC 27699- 1101 ( Old Revenue Building, 3rd Floor)
Telephone: ( 919) 807- 2899 Fax: ( 919) 807- 2902
For information concerning migrant housing inspections and other related activities contact:
Agricultural Safety and Health Bureau
Mailing Address: Physical Location:
1101 Mail Service Center 111 Hillsborough St.
Raleigh, NC 27699- 1101 ( Old Revenue Building, 2nd Floor)
Telephone: ( 919) 807- 2923 Fax: ( 919) 807- 2924
For information concerning occupational safety and health compliance contact:
Safety and Health Compliance District Offices
Raleigh District Office ( 313 Chapanoke Road, Raleigh, NC 27603)
Telephone: ( 919) 779- 8570 Fax: ( 919) 662- 4709
Asheville District Office ( 204 Charlotte Highway, Suite B, Asheville, NC 28803- 8681)
Telephone: ( 828) 299- 8232 Fax: ( 828) 299- 8266
Charlotte District Office ( 901 Blairhill Road, Suite 200, Charlotte, NC 28217- 1578)
Telephone: ( 704) 665- 4341 Fax: ( 704) 665- 4342
Winston- Salem District Office ( 4964 University Parkway, Suite 202, Winston- Salem, NC 27106- 2800)
Telephone: ( 336) 776- 4420 Fax: ( 336) 776- 4422
Wilmington District Office ( 1200 N. 23rd St., Suite 205, Wilmington, NC 28405- 1824)
Telephone: ( 910) 251- 2678 Fax: ( 910) 251- 2654
*** To make an OSHA Complaint, OSH Complaint Desk: ( 919) 807- 2796***
For statistical information concerning program activities contact:
Planning, Statistics and Information Management
Mailing Address: Physical Location:
1101 Mail Service Center 111 Hillsborough St.
Raleigh, NC 27699- 1101 ( Old Revenue Building, 2nd Floor)
Telephone: ( 919) 807- 2950 Fax: ( 919) 807- 2951
For information about books, periodicals, vertical files, videos, films, audio/ slide sets and computer databases contact:
N. C. Department of Labor Library
Mailing Address: Physical Location:
1101 Mail Service Center 111 Hillsborough St.
Raleigh, NC 27699- 1101 ( Old Revenue Building, 5th Floor)
Telephone: ( 919) 807- 2848 Fax: ( 919) 807- 2849
N. C. Department of Labor ( Other than OSH)
1101 Mail Service Center
Raleigh, NC 27699- 1101
Telephone: ( 919) 733- 7166 Fax: ( 919) 733- 6197

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A Guide to
Working with
Corrosive Substances
Thomas O’Connell
Series Editor
N. C. Department of Labor
Division of Occupational Safety and Health
1101 Mail Service Center
Raleigh, NC 27699- 1101
Cherie K. Berry
Commissioner of Labor
Acknowledgments
This edition of A Guide to Working with Corrosive Substances is
largely based on an earlier edition written by L. A. Weaver
Company, 308 East Jones Street, Raleigh, North Carolina. The L.
A. Weaver Company specializes in occupational safety.
Additional material was provided by North Carolina Department
of Labor Health Standards Officer J. Edgar Geddie, Ph. D.
Thank you to Tim Phillips, State Director of the Office of Motor
Carriers with the Federal Highway Commission of the USDOT,
and Cara Lucas, a NERL Environmental Compliance Officer
with EPA, for their review of the associated material.
This guide is intended to be consistent with all existing OSHA
standards; therefore, if an area is considered by the reader to
be inconsistent with a standard, then the OSHA standard
should be followed.
To obtain additional copies of this book, or if you have ques-tions
about N. C. occupational safety and health standards
or rules, please contact:
N. C. Department of Labor
Bureau of Education, Training and Technical Assistance
1101 Mail Service Center
Raleigh, NC 27699- 1101
Phone: ( 919) 807- 2875 or 1- 800- NC- LABOR
____________________
Additional sources of information are listed
on the inside back cover of this book.
____________________
The projected cost of the OSHNC program for federal fiscal year 2002– 2003 is $ 13,130,589.
Federal funding provides approximately 37 percent ($ 4,920,000) of this total.
Printed 7/ 99, 1M
N. C. Department of Labor
Occupational Safety and Health Program
Cherie K. Berry
Commissioner of Labor
OSHA State Plan Designee
Allen McNeely
Deputy Commissioner for Safety and Health
Kevin Beauregard
Assistant Deputy Commissioner for Safety and Health
Contents
Part Page
Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
1 What Are Corrosives? . . . . . . . . . . . . . . . . . . . . . . . . .11
2 What Regulations Protect Us
against Corrosives?. . . . . . . . . . . . . . . . . . . . . . . . . . .17
3 How Do Corrosives Harm Us and
How Can We Protect Ourselves?. . . . . . . . . . . . 12
Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
iii
Foreword
Employers must be aware of workplace hazards fac-ing
their employees and take appropriate action to min-imize
or eliminate exposure to these hazards. A Guide
to Working with Corrosive Substances discusses precau-tions
that can prevent serious health risks to workers
due to exposure to corrosives. Corrosive chemicals are
essential to many work processes; however, they can
enter the body through ingestion, inhalation, or contact
with the skin and eyes.
Employee exposure to corrosives must be evaluated
to determine the need for engineering and administra-tive
controls as well as the need for personal protective
equipment. The results from injuries can be severe and
even fatal. Mists produced by liquids can result in lung
damage if inhaled, serious burns or irritation can be the
result of accidental contact to the skin or eyes, and lung
and skin cancer have been linked to chromic acid.
Additional threats to employees are posed by the ease
with which many corrosive chemicals ignite, explode, or
react to incompatible substances.
In North Carolina, N. C. Department of Labor inspec-tors
enforce the federal Occupational Safety and Health
Act ( OSHA) through a state plan approved by the U. S.
Department of Labor. The N. C. Department of Labor’s
Division of Occupational Safety and Health ( OSHNC)
offers many educational programs to the public and
produces publications, including this guide, to help
inform people about their rights and responsibilities
regarding occupational safety and health.
iv
As you look through this guide, please remember that
OSHA’s mission is greater than just enforcement. An
equally important goal is to help citizens find ways to
create safe and healthy workplaces. Reading and using
the information in this booklet, like other educational
materials produced by the North Carolina Department
of Labor, can help.
Cherie K. Berry
Commissioner of Labor
v
1
What Are Corrosives?
Information about Corrosives from the
Department of Transportation
The United States Department of Transportation
( DOT) regulations consider a corrosive material to be
a liquid or solid that causes visible destruction or irre-versible
alterations in human skin tissue at the site of
contact, or in the case of leakage from its packaging, a
liquid that has a severe corrosion rate on steel. The DOT
further develops this definition by offering the following:
1. A material is considered to be destructive or to
cause irreversible alteration in human skin tissue if
when tested on the intact skin of the albino rabbit
the structure of the tissue at the site of contact is
destroyed or changed irreversibly after an exposure
period of four hours or less.
2. A liquid is considered to have a severe corrosion
rate if its corrosion rate exceeds 0.250 inches per
year on steel [ SAE 1020 ( Society of Engineers)] at
a test temperature of 130° F.
In most instances, corrosive materials may be identi-fied
by the label and/ or placard ( required by the DOT)
shown in figure 1.
Information about Corrosives from the
Environmental Protection Agency
The Environmental Protection Agency ( EPA), in regulat-ing
hazardous waste, uses pH as the criterion for determin-ing
if a substance is corrosive. Wastes with a pH of less
than 2.0 or greater than 12.5 are considered to be corrosive.
1
Figure 1
DOT Label for Corrosives
The EPA defines corrosive wastes to include ( 1) aque-ous
waste exhibiting a pH of less than or equal to 2 or
greater than or equal to 12.5 and ( 2) liquid waste capable
of corroding steel at a rate greater than 0.250 inches per
year ( 1/ 4 inches per year). The EPA chose pH as one
barometer of corrosivity because waste exhibiting low or
high pH can cause harm to human tissue, promote the
migration of toxic contaminants from other waste, react
dangerously with other waste, and harm aquatic life. The
EPA chose metal corrosion rate as its other barometer of
corrosivity because waste capable of corroding metal can
escape from the containers in which it is segregated and
liberate other waste.
The percent of acidity/ alkalinity provides an indica-tion
of the capacity of a waste to resist a change in pH.
That measurement aids in the assessment of the hazard
presented by a waste over the long term. However, it
adds little to the assessment of the hazard posed by
2
CORROSIVE
the waste during transportation, storage, and initial
disposal. Furthermore, because the capacity of a waste
to retain low or high pH is as much a function of its
disposal or storage environment as of its percent of
acidity/ alkalinity, there is no scientifically valid basis
upon which to establish hazardous threshold levels of
percent of acidity/ alkalinity. ( For additional information
see 40 CFR 261.22.)
All corrosive materials and solutions have the EPA
Hazardous Waste Number D002. The following are
some of the more commonly used corrosives:
Information about Corrosives from
Consensus Standard- Setting
Organizations
In 1956, the United Nations Committee of Experts on
the Transport of Dangerous Goods established a definition
of corrosives that is used by consensus standard setting
organizations, such as the International Labor Organiza-tion
and the Intergovernmental Maritime Organization.
[ Corrosives] are substances which, by chemical action
will cause severe damage when in contact with living
tissue or, in the case of leakage, will materially dam-age
or even destroy other freight or the means of
transport; they may also cause other hazards.
Another standard setting body, the Council of Europe,
3
• Acetic Acid
• Ammonium Hydroxide
• Chromic Acid
• Hydrobromic Acid
• Hydrochloric Acid
• Hydrofluoric Acid
• Nitric Acid
• Oleum
• Perchloric Acid
• Phosphoric Acid
• Potassium Hydroxide
• Sodium Hydroxide
• Sulfuric Acid
has established the following general classes of corrosives:
• Acids and Anhydrides
• Alkalis
• Halogens and Halogen Salts
• Organic Halides, Organic Acid Halides, Esters and
Salts
• Miscellaneous corrosive substances
The chemicals most often found in these classes are
listed in table 1.
Table 1
Council of Europe Corrosive Classification
4
Acids and Anhydrides:
Acetic Acid, Acetic Anhydride, Chlorosulphonic Acid, Chronic Acid,
Dichloroacetic Acid, Fluoboric Acid, Fluosilicic Acid*, Hydrobromic
Acid*, Hydrochloric Acid*, Hydrofluoric Acid*, Hydriodic Acid*,
Nitric Acid ( over 20%), Perchloric Acid ( over 10%), Phosphoric
Pentoxide, Priopionic Anhydride, Sulphuric Acid ( over 15%),
Oleum ( Fuming Sulphuric Acid), Trichloroacetic Acid
Alkalis:
Ammonium Hydroxide ( over 15% by weight of gas), Potassium
Hydroxide ( caustic potash), Sodium Hydroxide ( over 5%, caustic
soda)
Halogens and Halogen Salts:
Aluminum Chloride, Ammonium Difluoride, Antimony Trichloride
and Pentachloride, Bromine, Phosphorus Oxycholoride,
Phosphoryl Chloride, Phosphorus Trichloride and Pentachloride,
Potassium Difluoride, Sodium Difluoride, Sodium Hypochlorite,
Stannic Chloride, Sulphur Tetrachloride, Sulphuryl Chloride,
Thionyl Chloride, Titanium Tetrachloride, Zinc Chloride
Organic Halides, Organic Acid Halides, Esters and Salts:
Acetyl Chloride, Allyl Iodide, Benzoyl Chloride, Benzylamine,
Benzyl Chloroformate, Chloroacetyl Chloride
Miscellaneous Corrosive Substances:
Ammonium Polysulfide, 2- Chlorobenzadehyde, Hydrazine
( 1%– 4%), Hydrogen Peroxide ( over 20%), Silver Nitrate
* Over 25 percent concentration; Note: Mecuric Chloride, commonly called “ Corrosive
Sublimate,” is not considered to be a corrosive substance.
Acids and Bases
Acids and bases are a part of the classification of cor-rosives
and are chemicals that pose especially severe
risks if personal contact is made with them. An impor-tant
first step in understanding the effects of acids and
bases is clearly distinguishing the two terms. Acids are
those substances that yield hydrogen ions ( H+) in an
aqueous solution. Basic substances yield hydroxide ions
( OH–) in an aqueous solution. When acids and bases
are mixed they neutralize each other, producing salts.
The resultant solution has a salty taste and none of the
properties of either acids or bases.
Bases are also known as alkalis, caustics, or hydrox-ides.
As previously noted, both acids and bases are in a
broader group of materials known as corrosives. The
scale in table 2 illustrates the distinction.
Table 2
pH Scale
Substances with a pH of less than 7 are said to be
acidic. If the substance has a pH of more than 7, it is
basic. A neutral substance has a pH of 7.
5
RED GREEN BLUE
0 __________________________ 7 _________________________ 14
Acid Base
Caustic
Alkali
Hydroxide
NEUTRAL
Other distinguishing characteristics between acids
and bases include distinctions made by effects. Acids
are chemical compounds that show in water solution a
sharp taste. ( Of course, you should never actually taste
an acid to verify its effect.) Acids have corrosive action
on metals and turn certain blue vegetable dyes red. An
acid will turn blue litmus paper red.
Bases are chemicals that in solution are soapy to the
touch and turn red vegetable dyes blue. Red litmus
paper is turned blue by a base.
6
2
What Regulations Protect Us
against Corrosives?
The United States Department of
Transportation
Specific Department of Transportation ( DOT) regula-tions
regarding corrosives are in the Code of Federal
Regulations ( 49 CFR). Among DOT regulations are
requirements for the packaging and loading of corrosives
and guidelines for accidents where corrosives are
involved ( including the subject of leaking cargo tanks).
Regarding packaging, DOT requirements for
corrosives cover the outage. The expansion traits of the
liquid and the maximum increase of temperature to
which it will be subjected in transit determine the proper
vacant space ( outage or ullage) in the package. ( As a gen-eral
rule, sufficient outage must be provided so that the
packaging will not be liquid full at 130° F for packages of
less than 110 gallons, and for tank cars not less than 2
percent of the total volume). DOT regulations also apply
to the methods of closing and cushioning packaging and
the types of containers that may be used for corrosives.
The following summary of DOT regulations offers
general guidance regarding the loading of corrosive
liquids:
In general, individual carboys and frangible contain-ers
[ containers capable of being broken] of corrosive
liquids, including charged electric storage batteries,
must, when loaded by hand, be individually loaded
into and unloaded from any motor vehicle in which
they are to be transported. All reasonable precautions
must be taken to prevent the dropping of any such
7
containers or batteries containing corrosive liquids. No
such container or battery may be loaded into a motor
vehicle having an uneven floor surface. It shall be per-missible
to load corrosive liquids, more than one tier
high above any floor only if such carboys or other con-tainers
are boxed or crated, or are in barrels or kegs.
No carboy or other container of nitric acid shall be
loaded above any container containing any other kind of
material. The loading of carboys or other containers of
nitric acid shall be limited in height to two tiers.
The North Carolina Department of
Labor, Division of Occupational Safety
and Health
Safety and health standards enforced in North
Carolina must afford protection to employees which is
at least as effective as the protection afforded to
employees by federal occupational safety and health
standards. Each employer is responsible for knowing
the standards which apply to its industry.
The standards that apply to general industry and to
the construction industry in our state are published.
Standards may be found within the Code of Federal
Regulations ( CFR) 29 CFR 1910 for general industry
and 29 CFR 1926 for the construction industry. They
are also published under the titles of North Carolina
OSHA Standards for General Industry and North
Carolina Occupational Safety and Health Standards for
the Construction Industry.
The published standards and information, including
interpretations of the standards, may be obtained by
contacting the North Carolina Department of Labor,
Division of Occupational Safety and Health. ( See the
inside back cover of this guide for the address and tele-phone
number.)
8
Below, a list identifies ( but does not quote) statutes
and standards that afford employees protection against
hazards, including corrosives. The list is intended as
illustrative and representative rather than comprehen-sive.
N. C. Gen. Stat. 95- 129( 1)— requires each employer to
provide its employees work conditions and a workplace
free from recognized hazards which are likely to cause
serious physical harm.
29 CFR 1910- 94( d)— Ventilation— Open surface
tanks— includes ( but is not limited to) requirements for
ventilation and personal protection equipment ( such as
protective clothing and emergency showers and
fountains) for employees who work around open surface
tanks. ( See also 29 CFR 1910.261( g)( 18)( i); 29 CFR
1910.262( pp); 29 CFR 1910.268( b)( 2); 29 CFR
1910.111( b)( 10)( iii); 29 CFR 1910.111( b)( 10)( iv).)
29 CFR 1910.132— Personal Protective Equipment—
General requirements— requires protection for employ-ees’
eyes, face, head, and extremities in the presence of
hazards which require such protection, including ( but
not limited to) chemical hazards and hazards encoun-tered
through absorption, inhalation, or physical
contact. ( See also 29 CFR 1926.28.)
29 CFR 1910.133— Personal Protective Equipment—
Eye and face protection— requires protection against
liquids and other hazards to the eyes and face. ( See also
29 CFR 1926.102.)
29 CFR 1910.134— Personal Protective Equipment—
Respiratory protection— includes ( among other
pertinent subjects) the selection, fitting, and care for
respirators, and instructions to employees about the use
of respirators. ( See also 29 CFR 1926.103.)
29 CFR 1910.262( nn)— Special Industries— Textiles—
Acid carboys— regulates the safe removal of acid from
carboys.
9
29 CFR 1910.1000— Toxic and Hazardous
Substances— Air contaminants— identifies materials
and sets time limits for each material identified, beyond
which employees may not be exposed. ( See also 29 CFR
1926.55— Gases, vapors, fumes, dusts, and mists.)
29 CFR 1910.1200— Hazard Communication
Standard— requires that employees be informed of
chemical hazards in their workplace. ( See also 29 CFR
1926.59.) Some highlights of the standard follow:
✦ Employers must develop and implement a written
hazard communication program and make that
program available to employees.
The program must list all hazardous chemicals
known to be in the workplace and tell employees
about non- routine tasks ( such as cleaning out
tanks) which might expose them to the
hazardous chemicals.
✦ Containers of hazardous chemicals must be
labeled. The label must identify the chemical, its
manufacturer, and appropriate hazard warnings.
Employees must be trained to read such labels.
✦ Employers must have a material safety data sheet
( MSDS) for each hazardous chemical in its work-place.
The MSDS must include ( among other things):
the identity used on the container label; common
name and names of chemical ingredients in the
hazardous chemical; physical and chemical char-acteristics
( such as vapor pressure and flash
point); physical hazards ( such as potential for
fire, explosion, and reactivity to other substances
which are incompatible); health hazards ( such as
signs and symptoms of exposure); how the chem-ical
can enter your body; permissible exposure
limits; whether the chemical will cause cancer;
precautions for safe handling and use ( including
10
protective measures); emergency and first aid
procedures; when the MSDS was prepared or
last changed; the name and telephone number of
the manufacturer or other source which can
provide additional information ( including emer-gency
procedures).
✦ The MSDSs must be readily accessible to employees
during each work shift. Employees must be taught
to use them.
✦ Employees must be informed of the location of
hazardous chemicals.
✦ Employees must be trained in: how to detect the
presence of a hazardous chemical; its health haz-ards;
and protective measures ( including work
practices, personal protective equipment, and
emergency procedures).
11
3
How Do Corrosives Harm Us
and How Can We Protect
Ourselves?
How Corrosives Harm Us
Most commonly, the eyes, skin and digestive system
are the parts of the body affected by corrosive
chemicals. Causes include:
splashes during decanting
spills while carrying containers
splashes from reactions
vapors or streams from leaking containers
The severity is dependent primarily upon the concen-tration
of the chemical and the duration of contact.
With respect to the severity of chemical burns from
acids and alkalis, burns from alkalis tend to be the more
severe. An alkali in contact with human tissue may form
an albuminate ( clot or mass) and, with natural fats,
forms soaps. Tissue is gelatinized to form soluble com-pounds
resulting in deep and painful destruction.
Acids tend to harden the skin and produce pain at the
site of contact. Thus, they often give a quicker warning
of injury than do alkalis. First aid includes immediate
irrigation with plain water for at least 15 minutes.
In addition, mists produced by liquids can result in
lung damage if inhaled. Routine or accidental contact of
corrosives with the skin or eyes can result in serious
burns and irritation. Some acid mists, such as sulfuric,
can corrode teeth over an extended period of time.
Chromic acid is particularly dangerous and has been
linked to lung and skin cancer.
12
How We Can Protect Ourselves—
Evaluating the Workplace
Corrosive substances which present potential prob-lems
should be studied in detail to determine the
nature and seriousness of the problems they present.
A large part of this evaluation should consist of air sam-pling
conducted by an industrial hygienist or a person
trained in air sampling techniques. The possibility of
exposing employees to corrosives should be evaluated to
determine the needs for controls and personal
protective equipment.
Acids commonly found in industries include:
Industrial processes that use acids include:
metal cleaning, pickling, and etching
electrolysis
electroplating
battery making
paper making
chemical syntheses
Alkalis commonly found in industries include:
13
acetic
chromic
formic
hydrochloric
nitric
oxalic
perchloric
picric
phosphoric
sulfuric
ammonium hydroxide
barium
barium hydroxide
calcium chloride
calcium oxide ( quick-lime)
calcium sulfide
potassium hydroxide
sodium carbonate
( soda ash)
sodium hydroxide ( lye
or caustic soda)
sodium sulfide
Tests and Training for Employees Who
Work Near Corrosives
Recommended tests for employees exposed to corrosives
include pulmonary function tests, particularly forced vital
capacity ( FVC) and forced expiratory volume for one sec-ond
( FEV 1 ) and their ratio ( FEV 1 / FVC) on a scheduled
basis. Employees should be advised of the health hazards
posed by the particular corrosives with which they work.
They should be instructed in the proper procedures for
handling, transporting, and storing corrosives.
Training in the use of personal protective equipment
and the operation of engineering controls should also be
required.
Engineering and Administrative Controls
Engineering and administrative controls can be used
to reduce employee exposure to corrosive mists or dusts
in the air and to lessen the hazard of direct contact of
corrosives with the skin and eyes.
Engineering controls include:
local exhaust ventilation ( hoods or process enclosures)
dilution ventilation, or
a combination of the above
Administrative controls include:
eliminating the use of a particular corrosive
replacing one corrosive with a less toxic one
instituting procedures to reduce accidents associat-ed
with the handling, transporting, and storing of
corrosives
limiting employees’ exposure time to vapors, mists,
or dusts
14
One example of an administrative control is a precau-tion
to be taken when acids and water are mixed. The
acids should always be poured into the water, never the
opposite. This lessens the danger of acid being splashed
and of spattering from its contact with the water.
Figure 2 depicts apparatus designed for handling cor-rosive
liquids.
Personal Protective Equipment
When engineering and administrative controls have
failed to prevent or limit employees’ exposures, personal
protective equipment should be used. Depending on the
use of corrosives, the following types of equipment may
be required:
gloves and aprons for handling corrosives
eye and face protection against splashes
respirators for emergency or short- term use where
high concentrations of corrosives are present in the
air, and
protective shoe coverings
Emergency Wash Facilities
Additionally, emergency wash, routine washing facili-ties,
and overhead showers should be present in each
department or work area where corrosives are used.
The facilities should be in good working condition and
simple to operate. They should provide for a minimum
of 15 minutes of copious water flow. Table 3 summarizes
the requirements for eyewash and safety showers in
accordance with standards of the American National
Standards Institute ( ANSI Z358.1- 1990).
15
Figure 2
Apparatus for Handling Corrosive Liquids
16
Drum Pump Carboy Pump
Manual Pumps
Small
Bottle Tilter Carboy Tilter
Dispensing Aids
Drum Tilter Drum Dolly
Drum Handlers
17
Table 3
Summary of ANSI Z358.1- 1990— Key Requirements
Physical Features
Water column between 82"
and 96" within 20" mini-mum
diameter column at
60" above surface. Should
deliver 30 gallons per
minute ( gpm). Enclosures,
if used, require minimum
34" unobstructed diameter.
Flow rate of 0.4 gpm for 15
minutes required. Water
nozzles 33 to 45 inches
above floor and 6 inches
from wall or obstruction.
Not addressed.
Flow rate of 3.0 gpm for 15
minutes required. Water
nozzles 33 to 45 inches
above floor and 6 inches
from wall or obstruction.
Flow rate of 3.0 gpm
required.
Must meet physical
requirements of component
parts.
Equipment Type
Emergency
showers
Plumbed and
self- contained
Personal
eyewashers
Eye/ face
washes
Hand- held
drench hoses
Combination
units
Loca- Main- Training
tion tenance
* 1 * 3 * 6
* 1 * 4 * 6
* 2 * 5 * 6
* 1 * 3 * 6
* 1 * 3 * 6
* 1 * 3 * 6
*( 1) Accessible within 10 seconds and not over 100 feet from hazard.
*( 2) Not specified but recommended to be placed in vicinity of potentially
hazardous area.
*( 3) Activated weekly to flush lines and verify operation.
*( 4) Plumbed units activated weekly to flush lines and verify operation; self-contained
units- in accordance with manufacturer’s instructions.
*( 5) Inspected and maintained in accordance with manufacturers’ instructions.
*( 6) Required for all employees who might be exposed to a chemical splash.
18
Figure 3 provides examples of personal protective
equipment and emergency wash facilities.
Figure 3
Minimum Protective Equipment and Facilities
Chemical Goggles
Safety Goggles With
Full Face Shield
Eye/ Face Protectors
For Severe Exposures,
Chemical Goggles
With Full Face Shield
19
Personal Protective Equipment and Facilities
Checklist
In the checklist below, each item should be answered
“ yes.”
Are protective measures in place which:
Prevent skin, eye, and mucous membrane contact?
Provide personal protective equipment for body,
feet, head, hand/ arm, and eye/ face?
Provide properly maintained eyewash/ safety
showers for emergency use?
Ensure that workers are adequately informed and
trained as to precautions and controls?
Provide and require the use of personal hygiene
facilities at the conclusion of the work shift, prior
to breaks and meals?
Maintain corrosives in closed systems where possi-ble?
Ensure the avoidance of contact between
corrosives and other incompatible substances?
Provide for labeling on all containers as to their
content?
Provide ventilation, especially if corrosive gases or
dusts are present?
Provide fire preventive and protective measures if
contact with corrosives causes a fire risk?
Determine what risks from corrosives might be
generated from normal and abnormal
circumstances before a new process is introduced?
Ensure that acids are stored in fire- resistant
buildings with acid- resistant floors?
20
Provide storage areas with secondary containment
and proper drainage?
Provide acid- resistant electrical installations in
storage areas?
Protect glass and plastic containers against
impact?
Ensure that all containers are stored off the floor,
to facilitate flushing?
Require dispensing from larger containers with
carboy tilters and/ or pumps?
Terms
Albuminate. A water- soluble protein, widely occurring
in natural products such as milk, blood serum, and
eggs. It readily combines irreversibly to form a clot or
mass by the application of heat.
Anhydride. A chemical compound derived when a mole-cule
of water is eliminated from an acid.
Aqueous. Of, like, or formed by water.
Carboy. A large glass bottle, enclosed in a basketwork
or a wooden crate, and used for corrosive liquids.
Coefficient of Expansion. A coefficient for a substance,
which determines the extent which a solid body or gas
will expand when heat is applied.
Council of Europe. A consensus standard- setting orga-nization.
Ester. Organic compounds ( those containing carbon)
corresponding to an inorganic salt and formed by the
reaction of an acid and an alcohol.
Halide. A compound containing two elements of the
halogens.
Halogen. One of the very active chemical elements of
Group VII A of the periodic table: fluorine, chlorine,
bromine, iodine, astatine.
ILO. International Labor Organization— a consensus
standard- setting organization.
IMO. Intergovernmental Maritime Organization—
a consensus standard- setting organization.
Litmus Paper. Strips of paper containing blue
amorphous powder. The paper changes color with the
acidity or alkalinity of a solution— red at pH 4.5, blue at
pH 8.3.
21
Negative Logarithm. A common logarithm is the index
of a power to which the base 10 must be raised to equal
the number. A negative logarithm is when the charac-teristic
is less than one. Example:
Log 10 ( x) = 0.0254 means 10x = 0.254
x = - 1.59517
Outage. A vacant space left in an enclosed container to
allow for substances with high coefficients of expansion
to expand as they are heated. Such substances include
compressed gases, corrosives, and flammables. The
terms “ freeboard” and “ ullage” are also used.
pH Value. The strength of an acid or base is expressed
by the pH value. The pH is the negative logarithm of
the hydrogen ion concentration and will usually be in
the range of 1– 13. This is because the actual hydrogen
ion concentration values would otherwise cover too wide
of a range to provide meaningful data.
22
The following industry guides are available from the N. C. Department of Labor’s Division of Occupational
Safety and Health:
1# 1. A Guide to Safety in Confined Spaces
1# 2. A Guide to Procedures of the Safety and Health Review Board of North Carolina
1# 3. A Guide to Machine Safeguarding
1# 4. A Guide to OSHA in North Carolina
1# 5. A Guide for Persons Employed in Cotton Dust Environments
1# 6. A Guide to Lead Exposure in the Construction Industry
1# 7. A Guide to Bloodborne Pathogens in the Workplace
1# 8. A Guide to Voluntary Training and Training Requirements in OSHA Standards
1# 9. A Guide to Ergonomics
# 10. A Guide to Farm Safety and Health
# 11. A Guide to Radio Frequency Hazards With Electric Detonators
# 12. A Guide to Forklift Operator Training
# 13. A Guide to the Safe Storage of Explosive Materials
# 14. A Guide to the OSHA Excavations Standard
# 15. A Guide to Developing and Maintaining an Effective Hearing Conservation Program
# 17. A Guide to Asbestos for Industry
# 18. A Guide to Electrical Safety
# 19. A Guide to Occupational Exposure to Wood, Wood Dust and Combustible Dust Hazards
# 20. A Guide to Crane Safety
# 21. A Guide to School Safety and Health
# 23. A Guide to Working With Electricity
# 25. A Guide to Personal Protective Equipment
# 26. A Guide to Manual Materials Handling and Back Safety
# 27. A Guide to the Control of Hazardous Energy ( Lockout/ Tagout)
# 28. A Guide to Eye Wash and Safety Shower Facilities
# 29. A Guide to Safety and Health in Feed and Grain Mills
# 30. A Guide to Working With Corrosive Substances
# 31. A Guide to Formaldehyde
# 32. A Guide to Fall Prevention in Industry
# 33. A Guide to Office Safety and Health
# 34. A Guide to Safety and Health in the Poultry Industry
# 35. A Guide to Preventing Heat Stress
# 36. A Guide to the Safe Use of Escalators and Elevators
# 37. A Guide to Boilers and Pressure Vessels
# 38. A Guide to Safe Scaffolding
# 39. A Guide to Safety in the Textile Industry
# 40. A Guide to Emergency Action Planning
# 41. A Guide to OSHA for Small Businesses in North Carolina
Occupational Safety and Health ( OSH)
Sources of Information
You may call 1- 800- NC- LABOR ( 1- 800- 625- 2267) to reach any division of the N. C. Department of Labor; or visit the
NCDOL home page on the World Wide Web, Internet Web site address: http:// www. nclabor. com.
N. C. Division of Occupational Safety and Health
Mailing Address: Physical Location:
1101 Mail Service Center 111 Hillsborough St.
Raleigh, NC 27699- 1101 ( Old Revenue Building, 3rd Floor)
Local Telephone: ( 919) 807- 2900 Fax: ( 919) 807- 2856
For information concerning education, training and interpretations of occupational safety and health standards contact:
Bureau of Education, Training and Technical Assistance
Mailing Address: Physical Location:
1101 Mail Service Center 111 Hillsborough St.
Raleigh, NC 27699- 1101 ( Old Revenue Building, 4th Floor)
Telephone: ( 919) 807- 2875 Fax: ( 919) 807- 2876
For information concerning occupational safety and health consultative services and safety awards programs contact:
Bureau of Consultative Services
Mailing Address: Physical Location:
1101 Mail Service Center 111 Hillsborough St.
Raleigh, NC 27699- 1101 ( Old Revenue Building, 3rd Floor)
Telephone: ( 919) 807- 2899 Fax: ( 919) 807- 2902
For information concerning migrant housing inspections and other related activities contact:
Agricultural Safety and Health Bureau
Mailing Address: Physical Location:
1101 Mail Service Center 111 Hillsborough St.
Raleigh, NC 27699- 1101 ( Old Revenue Building, 2nd Floor)
Telephone: ( 919) 807- 2923 Fax: ( 919) 807- 2924
For information concerning occupational safety and health compliance contact:
Safety and Health Compliance District Offices
Raleigh District Office ( 313 Chapanoke Road, Raleigh, NC 27603)
Telephone: ( 919) 779- 8570 Fax: ( 919) 662- 4709
Asheville District Office ( 204 Charlotte Highway, Suite B, Asheville, NC 28803- 8681)
Telephone: ( 828) 299- 8232 Fax: ( 828) 299- 8266
Charlotte District Office ( 901 Blairhill Road, Suite 200, Charlotte, NC 28217- 1578)
Telephone: ( 704) 665- 4341 Fax: ( 704) 665- 4342
Winston- Salem District Office ( 4964 University Parkway, Suite 202, Winston- Salem, NC 27106- 2800)
Telephone: ( 336) 776- 4420 Fax: ( 336) 776- 4422
Wilmington District Office ( 1200 N. 23rd St., Suite 205, Wilmington, NC 28405- 1824)
Telephone: ( 910) 251- 2678 Fax: ( 910) 251- 2654
*** To make an OSHA Complaint, OSH Complaint Desk: ( 919) 807- 2796***
For statistical information concerning program activities contact:
Planning, Statistics and Information Management
Mailing Address: Physical Location:
1101 Mail Service Center 111 Hillsborough St.
Raleigh, NC 27699- 1101 ( Old Revenue Building, 2nd Floor)
Telephone: ( 919) 807- 2950 Fax: ( 919) 807- 2951
For information about books, periodicals, vertical files, videos, films, audio/ slide sets and computer databases contact:
N. C. Department of Labor Library
Mailing Address: Physical Location:
1101 Mail Service Center 111 Hillsborough St.
Raleigh, NC 27699- 1101 ( Old Revenue Building, 5th Floor)
Telephone: ( 919) 807- 2848 Fax: ( 919) 807- 2849
N. C. Department of Labor ( Other than OSH)
1101 Mail Service Center
Raleigh, NC 27699- 1101
Telephone: ( 919) 733- 7166 Fax: ( 919) 733- 6197